NEW YORK, July 30 (Reuters) - Closely followed bond investor Bill Gross on Thursday said the Federal Reserve is beginning to recognize that ultra low interest rates increasingly have negative as well as positive consequences.

Gross’ remarks in his August Investment Outlook came a day after the Fed, at the conclusion of its two-day policy meeting, left its benchmark short-term interest rate near zero but dropped several hints that it is near seeing enough improvement in the job market to prompt officials to raise the rate as early as September.

The roughly $7 trillion that the world’s three biggest central banks, including the Fed, have pumped into the financial system since the financial crisis has succeeded mostly in lifting prices of securities rather than the cost of goods and workers’ wages, Gross said.

Gross, who runs the Janus Global Unconstrained Bond Fund , wrote that low interest rates have enabled Corporate America to borrow hundreds of billions of dollars “but instead of deploying the funds into the real economy, they have used the proceeds for stock buybacks.”

Corporate authorizations to buy back their own stock are running at an annual rate of $1.02 trillion so far in 2015, 18 percent above 2007’s record total of $863 billion, Gross said.

“If a central bank could lower the cost of debt and equity closer and closer to zero, then inevitably the private sector would take the bait - investing in cheap plant and equipment, technology, innovation - you name it. ‘Money for nothing - get your clicks for free’, I suppose,” Gross wrote. “But no. Not so.”

What was equally troubling, Gross said, is that because double-B and single-B rated and in some cases triple-C rated companies have been able to borrow at less than 5 percent, “a host of zombie and future zombie corporations now roam the real economy.”

Gross pointed to a recent annual report by the Bank for International Settlements, the central banks’ central banker, which warned there are substantial medium term costs of “persistent ultra-low interest rates.”

Such rates, the BIS claims, “sap banks’ interest margins...cause pervasive mispricing in financial markets...threaten the solvency of insurance companies and pension funds...and as a result test technical, economic, legal and even political boundaries,” Gross said.

Gross said the BIS report does not specifically mention Greece, nor the roller coaster ride of Chinese equity markets, nor the rising illiquidity of global high yield bond markets. “Low interest rates may not cure a fever - they may in fact raise a patient’s temperature to life threatening status,” Gross said. (Reporting By Jennifer Ablan; Editing by Chizu Nomiyama)